Table 2.

Critical appraisal of nonrandomized studies.

Lead Author (Year)	Level of Evidence	MINORS Score a
Fickert (2012) [15]	2b	11
Siebold (2014) [16]	4	9
Siebold (2016) [17]	4	8
Siebold (2018) [18]	4	12
Hoburg (2019) [19]	3b	19 *
Grevenstein (2020) [20]	4	8
Niemeyer (2020) [21]	2b	22 *
Sumida (2021) [22]	3b	8

^a Methodological Index for Nonrandomized Studies (MINORS) scores were out of a possible ideal of 16 for noncomparative studies and 24 for comparative studies (*). The levels of evidence are explained in the legend of Table 1.